change the curlRequest call to options array and build the options array
there.
Remove any options check + pre build from the get/request calls
Update phpunit tests with string type body return
Removed the parseHeaders public call, headers must be set as array
Throw errors on invalid headers before sending them: Key/Value check
Add headers invalid check in phpunit
Auth headers can be set per call and will override global settings if matching
Instead of just throwing exception on 401 auth, throw exception for any
error code from 400 on
This can be turned off with the option "http_errors" set to false
Also updaed the exception content to match 400 or 500 error type with
more information attached
General Exception error codes:
Cnnn: Curl errors (FAILURE)
Rnnn: general class errors (ERROR)
Hnnn: http response errors (ERROR)
